Annihilation of stacking faults in beta-SiC was found to occur simultaneously with grain growth during high-temperature sintering. Analyzes of the rate process by use of the Avrami-Erofeev equation indicated that the rate of annihilation of stacking faults was controlled by the atomic diffusion process. The rate of grain growth, on the other hand, was found to be limited by surface diffusivity. Coincidence in the values of activation energy for the two processes suggested that the annihilation of stacking faults is an apparent phenomenon resulting from the microstructural evolution in which the grain growth is controlled by surface diffusivity. Incorporation of nitrogen during heating suppressed the surface diffusivity and hence, the rate of stacking fault annihilation. Formation of stacking faults during the synthesis of beta-SiC by cabothermal reduction of silica was also investigated and we found that two kinds of morphology, whisker and sphere, were always observed for the synthesized powder, and that a larger amount of stacking faults were containde in whiskers than in spherical particles.